Affiliation: | (1) Department of Diagnostic Imaging, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada e-mail: paul.babyn@sickkids.on.ca Tel.: + 1-4 16-8 13 55 27 Fax: + 1-4 16-8 13 75 91, CA;(2) Department of Pediatrics, Division of Rheumatology, Hospital for Sick Children, and University of Toronto, Toronto, Ontario, Canada, CA |